Is your feature request related to a problem? Please describe.
When editing or adding tasks on the frontend, it’s hard to remember which items were modified locally but not yet synced with the backend (CLI). This can cause confusion about what’s already pushed and what’s still pending.

Describe the solution you'd like

1. Whenever a task is added or edited on the frontend:
2. Mark it visually with an icon, color tag, or subtle indicator (e.g., 🟡 dot, ✏️ symbol, or “unsynced” badge).
3. These indicators clearly show which items have been modified on the frontend but not yet synced.
4. After a successful sync with the backend, CCSync should reset all these indicators, so the user knows everything is now synced and clean.

Describe alternatives you've considered

1. Keeping track mentally (error-prone).
2. Relying on timestamps (not intuitive in UI).

Additional context

1. Could be implemented as a small visual overlay or CSS class change on task cards/lists.
2. Optionally, hovering over an unsynced task could show “Pending sync…” tooltip.

Impact
Improves developer and user clarity at a glance, one can see what’s new or modified locally.
Makes syncing feel transparent and reliable, especially during active development cycles.